Sheet for making cushion disks and method of making same



March 9 1926. A 1,576,242

` c. E. McMANuvs lSHEET FOR MAKING CUSHION DISKS AND METHOD 0F MAKING SAME Filed August 29, 1923 m mm gh @MME Y,

Patented Mar., 9,' i926@ untreu stares parent onirica,

cuantas n. McManus, or new Yoann., r.

SHEET EGE MAKING USHION DISKS AND METHOD 01E' MARN@ SAME.

Applicatidn led August 29, 1923. Serial No. 659,894.

To all 'whom t may concern: l

Be it known that l, CHARLES E. MoMAN- Us, a citizen of the United States, residing in the borough of Manhattan, city, oounty, and State of New York, have invented certain new and useful :improvements in Sheets for Making Cushion Disks and Methods of Making Same, of which the following is a specification, reference being had therein to the accompanying drawings, which form a part thereof.

My invention relates to a sheet-of elastic, substantially non-absorbent material, composed mainly of cork, which sheet has a thickness which will permit cork disks to be out therefrom, to be used in closure caps for sealing bottles, and to the method of producing same, l

lt has longbeen the practice in the manufacture of bottle closures, of the crimped met-al shell, as well as other types, to use cushion disks formed either of natural cork wood, or of composition cork, a material formed of granulated cork Waste, the granules of which have been thinly coated with an adhesive or cement before being compacted and bonded to form a homogeneous product.

Because of the extreme care required in selecting the natural cork disks in order to avoid the presence of pores of suflicient magnitude to cause what is known as leakers due to passages at the lip of the bottle, even when a cap containing a disk is applied thereto with considerable pressure; the demand for composition cork disks is progressively increasing, so that at the\ present time, it is possibly greater than that for the natural cork. This may bel attributed to the fact that composition cork is practically lacking in voids corresponding with the pores of the natural cork, possesses relatively higher elasticity and is of substantially uniform density and elasticity throughout. The composition cork disks have the disadvantages however,

of`having less durability than the natural cork' disk, owing to the tendency of the cork composition to soften when subjected to the action of liquids for a. prolonged period and of having a darker color than the natural cork and a tendency to disoolor more rapidly than same.

While suchcharacteristics are present in composition cork, the life of a disk made therefrom is sufcient topermit itsl use with manybeverages, although, with certain beverages, it has been found necessary to appose the composition cork about same in a N positionl where it will seat against the lip of the bottle, and yet not be exposed to contact with the liquid' within the bottle.

By my invention, l provide a resilient sheet for making cushion disks which will possess all the advantages of the natural cork and also of the composition cork and possesses none of the disadvantages of the latter. 'lhe disk forming sheets embodying my invention are composed mainly of composition cork, having one surface of natural cork so that disks made therefrom may be handled in a bottle cap assembling machine in the same manner as the ordinary natural or composition cork disks so as to avoid any additional operations in the production of bottle caps from such disks.

'lhe composition cork, when in the cap, is presented towards the metal or the shell, as its lacquered surface, so as to facilitate the bonding or cementing of the disk to the shell and afford to the natural cork surface a backing of relatively higher elasticity than is found in natural cork. The thinness of the natural cork surface increases itsv flexibility as compared with cork of a greater thickness so that full advantage may be taken of the increased elasticityv of the composition cork without likelihood of the natural cork surfaces breaking or cracking and forming `channels or passages as a result of thepressure applied to the cap, a bottle.

The method of mv present inventionl is applicable to the production of sheets utilizing cork of the first quality only, other methods being required when cork of lower grade is used. e

In referring to cork of different grades, I have reference not only to the ago at which when placing it upon the cork is harvested, 'but to the different portions of cork, irrespective of its age. The ideal age of cork for use in bottle caps is from six to eight years, but generally at this period o nly one half of the thickness of the cork can be advantageously used, owing tothe fact that the fibres at different stages of the development of the cork in process of growth develops pores which are progressively increased in magnitude toward the outer bark. This outer bark of itself, is so hard, brittle, and irregular as to be practically a waste product. The inner laminations of the cork are substantially freefrom pores of a depth which will interfere with the use of this portion of the cork in making cushion disks.

The method of my invention and resulting product has to do with the utilization of this portion of the cork, or corkof the first grade only. A sheet embodying my inven-v tion, and the method of making such a sheet, have the further advantage that since the composite product will be of the same Blickness as the ordinary cork disks, whether the same be made entirely of natural cork or of composite cork, and since the backing of composition cork is of relatively greater thickness than the surface of the natural cork, the quantity of the natural cork is only a small percentage of that required, when a greater thickness of natural cork is used,

which is a matter of considerable importance not only as to the cost of the product, but as to the conservation of the natural cork, of which the supply is limited.

The invention consistsl primarily of a sheet for making cushion disks consisting of a stratum composed df granules of cork bonded together by a. thin coating of adhesive, its surface consisting of a thin sheet of natural cork having substantially no voids therein and means bonding said sheet of natural cork to said composition cork stratum; and in such other novel characteristics and in the novel steps and practice in the production of said sheets, all as heretofore set forth and described and more particularly pointed out in the claims hereto appended.

Referring to the drawings;

Fig. 1 is a perspective view of a part of the stratum of the composition cork entering into the sheet;

Fig. 2 is a similar view of the thin sheet of natural cork;

Fig. 3 is a side view of the completed product, and v Fig. 4 is a view similar to Fig. 3 illustrating another embodiment of the invention,

A composite cork sheet, as shown in the drawing is preferably used only for the highest grade of cushion disks, and I prefer to use only a high grade of natural cork and a composition cork containing high grade natural cork waste therein. I

deslrd however, lower grade of natural cork and cork waste may be used, but the product will not be as uniform and there will be greater likelihood of leakers when bottle caps containing disks made` therefrom are in use.

In the drawings, a indicates a stratum of composition cork, composed of granulated cork, the separate granules of which have -a thin coating of any suitable and well known adhesive and the mass of which is thereafter rolled or pressed to secure the desired thickness of and density in the stratum. Vhen so formed one surface thereof is coated with a suitable adhesive stratum b and a thin sheet c of natural cork laid thereon. Thereafter pressure is applied to secure the desired intimate engagement of the material ofthe stratum a and the sheet c as in ordinary gluing, while heat is being applied to hasten the proper conditioning of the adhesive. f

Ordinarily the thickness of the stratum a, w-ill4 be at least three times that of the sheet c although the relative cross sectional areas of the two may be varied, while securing satisfactory results. Furthermore if desired the stratum of composition cork may be sliced from a seasoned slab of this material before superimposing the sheet of natural The thickness of the composite sheet a, b

and c for making cushion disks in approximately one tenth of an inch, so that it is possible to procure forty sheets of natural cork from'one inch of cork bark and thais permit the production from a given quantity of natural cork, of four times the quantity of cushion disks, which could be produced from the same quantity of cork bark if lsolid natural cork disks were made therefrom.

I preferably use cork sheets cut about one fortieth of an inch in thickness since in the higher grades of cork, i. e. the portions more remote from the outer shell or bark, there will seldom be pores or voids of a depth which will extend through this thickness. If the sheets can be cut thinner it would be preferable since the thinner the sheet, the greater its flexibility and the less the likelihood of its cracking or breaking when it is brought with pressure into engagement with the neck of a bottle.

After the cork is cut into sheets as described, it is treated in the usual manner to remove -any superficial impurities or grit.

The method of my presentinvention, contemplatesthe formation of the stratum a prior tothe application and bonding of the surfacing sheet thereto, the application `of heat and pressure @simultaneously bake nur prefer, however', to use for the stratum a,

composition cork, which has been sliced from a slab of compacted, and backed and scasoned composition cork.

'lliecompleted cork sheet composed of a stratum of composition cork, and a sheet of relatively thinner natural cork, having a high vdegree of dekibility but relatively less elasticity than said stratum of composition cork, isy an ideal material from whichto make cushion disks. The great elasticity of the composition cork stratum permits the iirm seating of the disk upon theneck of a bottle, and the relatively less elasticity and great ilexibility of the surface sheet of natural cork permits the face of the disk presented towards the bottle, conforming accurately with the neck of the bottle and withfthe depression formed in the composition cork stratum. rlhe vnatural cork sheet will protect the composition cork stratum from atmosphere and from the contents of a bottle and will prevent any discoloration from age or long .use on a bottle, beyond that which natural cork is subject to. lin fact cork disks made from such a sheet have all the characteristics of a disk made solely of natural cork, but possesses greater elasticity, so that they will seat more closely against the neck of a bottle and thus minimize the likelihood of leakers4 as compared with disks made wholly of natural cork.

The substantially uniform density of the stratum will serve as an impermeable barrier between the natural cork surfacing and the metal of the shell carrying the disk and avoid the necessity for using a paper collet to prevent liquider gases entering between the disk and said shell.

lin the embodiment of my invention, shown in Fig. t, l employ a sheet d of paper or other similar material firmly 4cemented to the face of the stratum a opposite that to which the cork sheet o is bonded so that when disks are -cutfrom the sheet, each disk will embody therein its own paper collet firmly Vbonded thereto. lf desired this paper sheet d may have a coat of adhesive or glue in a dry state upon its exposed surface to facilitate the assembling vof the disk in its metal shell.

lVhile l have shown certain relative dimensions of the stratum a and sheet c in the accompanying drawings and have herein given certainspecific dimensions thereof, by way of example, itis apparent that such d1- mensions may vary according to the quality of the natural cork from which the sheets o are sliced, any variation in the thickness of said sheet necessitating a converse variation is that @t Said stratum a li have also referred herein to the conser yation of natural cork, resulting from the increased number of disks which can be produced from natu-ral cork when thin sheets of such are used for -surfacing a composition Vcork stratum, for making disks in lieu of solid natural'cork. Since sheets embodying my invention consists mainly of cork either in sheet or granular form, it is apparent that such conservation results from the fact that the composition cork is made from waste or scrap ,from the manufacture of other cork articles, thus not increasing the demand for cork bark.

It will be noted that in cutting a cork disk from a llarger sheet, this disk becomes merely a smaller sheet of articular' contour ,havipg all of the characteristics of the larger s ee Having described the linvention what ll claim as new, and desire to have protected by Letters Patent is '1. A sheet for making cushion'disks consisting of a stratum composed of granules of cork bonded together by a thin coating of adhesive, a surface consisting of a thin sheet Aof natural cork having substantially no voids therein, and means bonding said sheet of natural cork to said composition cork stratum. l

v 2. A sheet for making cushion diskscon` sisting of a stratum composed of granules of cork bondedltogether by a thin cpating of adhesive, and having high elasticity,.a sheet of natural cork of relatively less thickness than said stratum whereby it will have the elasticity of natural cork and relatively increased exibility than natural cork of greater thickness, said sheet of natural cork having substantially no voids therein, and means bonding said sheet of natural cork to said compositionV cork stratum.

3. A sheet for making cushion disks con- `sisting of a stratum composed of granules of cork bonded together by a thin coating of adhesive, a thin sheet of natural cork having substantially novoids therein bonded to one surface thereof, and a'gummed sheet of collet forming material bonded to .the opposite side thereof.

4. The herein described method of making a `sheet for makin cushion disks consisting in compacting an bonding together a mass of cork granules each having a thin coating of adhesive, to form a sheet of composition p cork applying adhesive to one surface of said sheet, laying a relatively thin sheet of natural cork having substantially 11o voids therein, upon the adhesive coated surface of composition cork, and applying heat and pressure thereto to bond the two sheets to'- gether to form a unitary sheet. 5. The herein described method of mak ing a sheet for making cushion disks corrsistiug in ot'mng Sleb 0f compacted,

sal

los

baked and seasoned composition cork consistin of cork granules having a, thin coating o adhesive, slicing said slab into sheets of a thickness less than the thickness of cushion disks, applying adhesive to one Surface of a sheet so formed, laying a relatively thin sheet of natural cork having substantially no voids therein, upon the adhesive coated l I surface of composition cork, and applying heat and pressure thereto to-bond the two 10 sheets together to form a unitary sheet.

In witness whereof I have hereunto axed my signature this 24th day of August, 1923.

CHARLES E. MCMANUS. 

